Races like the Tough Mudder and Warrior Dash are exploding in popularity. We asked two of the sport's top athletes about the gear that helps them get onto the podium.

Barbed wire. Mud pits. Jacked "gladiators" armed with cudgels. Obstacle racers face a lot of stumbling blocks on their way to the finish line. The sport, which pairs a footrace with Navy SEAL-style challenges, is hitting critical mass in this country, with thousands of athletes signing up for mud-caked events like the Spartan Race, Tough Mudder, and Warrior Dash. For a primer on the best gear for the sport, we interviewed two champion racers: Hobie Call, the most successful Spartan Racer of all time, and Margaret Schlachter, a Vermont-based athlete with top finishes in races like the Warrior Dash and Tough Mudder New England. This is the gear that helps them get to the podium.